I have a column in my JavaFX TableView where the value is just a color based on some other value. For this I use a custom TableCell to fill the color.

This works fine unless I refresh the items in the TableView. In that case cell just displays transparent or maybe nothing…

I created a sample to demonstrate this:

2 files:

import javafx.application.Application;
import javafx.beans.property.ListProperty;
import javafx.beans.property.SimpleListProperty;
import javafx.collections.FXCollections;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.paint.Paint;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;

import java.util.Random;

public class ColorCellTest extends Application {


    private final ListProperty<CellData> items = new SimpleListProperty<>(FXCollections.observableArrayList());
    private final TableView<CellData> tableView = new TableView<>();

    @Override
    public void start(Stage primaryStage) throws Exception {
        BorderPane root = new BorderPane();
        Scene scene = new Scene(root, 800, 600);

        fillItems();

        tableView.setColumnResizePolicy(TableView.CONSTRAINED_RESIZE_POLICY_ALL_COLUMNS);
        tableView.setColumnResizePolicy(TableView.CONSTRAINED_RESIZE_POLICY_ALL_COLUMNS);

        TableColumn<CellData, String> statCol = new TableColumn<>(" ");
        statCol.setMaxWidth(20);
        statCol.setCellFactory(param -> new ColorCell());
        tableView.getColumns().add(statCol);

        TableColumn<CellData, String> textCol = new TableColumn<>("Text");
        textCol.setCellValueFactory(new PropertyValueFactory<>("text"));
        tableView.getColumns().add(textCol);

        tableView.setItems(items);

        root.setCenter(tableView);

        Button button = new Button("Refresh");
        button.setOnAction(event -> refreshItems());
        root.setBottom(button);

        primaryStage.setScene(scene);
        primaryStage.setTitle("ColorCellTest");
        primaryStage.show();
    }

    private void fillItems() {
        System.out.println("fill items");

        Random random = new Random();

        for (int j = 0; j < 20; j++) {
            char c = (char) (random.nextInt(3) + 65);
            String stat = Character.toString(c);
            String text = "Text " + stat;
            items.add(new CellData(stat, text));
        }
    }

    private void refreshItems() {
        System.out.println("refresh items");
        items.clear();
        fillItems();
    }

    private static class ColorCell extends TableCell<CellData, String> {

        private final Circle overlay;

        public ColorCell() {
            overlay = new Circle();
            overlay.setFill(Color.TRANSPARENT);
            overlay.setRadius(4);

            StackPane pane = new StackPane();
            pane.getChildren().addAll(overlay);
            setGraphic(pane);
        }

        @Override
        protected void updateItem(String item, boolean empty) {
            super.updateItem(item, empty);

            super.updateItem(item, empty);
            if (!empty) {
                if (getTableRow() != null) {
                    CellData currentRowValue = getTableRow().getItem();
                    if (currentRowValue != null) {
                        System.out.println("fill:" + currentRowValue.getText() + " " + currentRowValue.getStatus());
                        Paint paint = switch (currentRowValue.getStatus()) {
                            case "A" -> Color.GREEN;
                            case "B" -> Color.BLUE;
                            case "C" -> Color.RED;
                            default -> null;
                        };
                        overlay.setFill(paint);
                    }
                }
            } else {
                setGraphic(null);
                setText(null);
            }
        }
    }

}

CellData class

public class CellData {
    private String status;
    private String text;

    public CellData() {
    }

    public CellData(String status, String text) {
        this.status = status;
        this.text = text;
    }

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public String getText() {
        return text;
    }

    public void setText(String text) {
        this.text = text;
    }
}

All I’m doing is creating a custom TableCell class which draws a circle of a color based on the status.

This works until you refresh the list.

Any ideas?

TIA

jdk-22.0.1
JavaFX 22